How To Spot An Authentic Tiffany Lamp

“Out of 100 emails I get, probably just 4 or 5 percent of them are authentic,” says Dennis Tesdell, a private Tiffany lamp broker and consultant who assess lamps through his website AntiqueTiffanyLamps.com.

“It’s become a phrase. Any leaded lamp is called a Tiffany lamp,“ adds auctioneer John Fontaine, of Fontaine's Auction Gallery, who has been in the business for 42 years.

Fontaine gets about 50 calls a week to verify if a lamp is a real Tiffany. Most are not the real thing.

What they're hoping they have—a genuine Tiffany lamp—could be worth a small fortune. The originals, those made in the 1890s to 1930s by Tiffany Studios under the watchful eye of Louis Comfort Tiffany, can be worth anywhere from $4,000 to over $1 million. The most ever paid for an original was $2.8 million in 1997 at a Christie's auction.

“Floral lamps command the most money,” says Jeni Sandberg a specialist in 20th century decorative arts at Christie’s. “Intense colors are what people favor. Geometric lamps are generally worth less than the floral lamps.” (See Tiffany lamps up for auction in our slideshow.)

Imitations are common. Several companies mimicked the Tiffany lamp style in the 1920s with cheaper, lesser quality models. In the past 30 to 40 years, forgeries have hit the market that can fool collectors and experts alike.

So what to do if you think you have a Tiffany lamp in your possession? Ultimately, you’ll need to bring it to an expert who has years of experience dealing with them.

Because Tiffany produced a lot of custom-made lamps, there aren’t many hard rules. It’s more of a combination of factors when it comes to authentication. But if you’re staring at a lamp in your home or at an estate sale or antique shop, look for these characteristics to help determine if it is an original.

The base: Tiffany almost always made its lamps with a bronze base. There were no wood, plastic, brass or zinc bases, says Tesdell, which are common with cheaper versions. Very rarely, however, art pottery bases were made.

The glass: Tiffany Studios mostly made its high-quality glass in New York, says Sandberg. Tiffany used a couple of techniques that makes their lamps stand out.

One is confetti glass, where specks of different colors are used on one of the many pieces of glass. Secondly the color of the glass actually changes when the lamp is lit.

Its origins: If you’re in an antique shop or other sale, ask the seller to tell you who the previous owner was. If it came from an estate or was owned for the past 40 to 50 years by the same person, there's a better chance it’s a real Tiffany lamp, says Fontaine.

People typically come upon authentic ones through their family, says Sandberg; either they inherit it or discover it in a basement or attic. It's more rare, but some have found originals at antique shops and estate sales.

Stamps: The base of Tiffany lamps almost always carried a Tiffany Studios stamp with a number. Many of the glass shades were also stamped. It’s also important to remember that an item stamped Tiffany & Co., the high-end jewelry and fine goods shop, is not the same. The lamps made by Louis Comfort Tiffany were stamped Tiffany Studios New York.

Signs of age: An authentic lamp won’t look brand new. There will be what is called patina—fading or small color changes on the bronze parts of the lamp. But even this is not always fool proof. Really good reproductions, Fontaine says, mimic age on the base.

Light socket: Tiffany Studios usually made its lamps with a turn-paddle knob socket for on and off purposes, says Sandberg. A smaller number were made with a pull chain. Mostly, says Sandberg, companies such as General Electric, Bryant and Perkins made the sockets. A socket that has been changed could effect value. Some Tiffany lamps can also have a turn switch at the base.

Lead filling. Because of the high cost of bronze when the lamps were being made, Tiffany Studios made their bases hollow, says Fontaine. In order to support the heavy glass shades, a heavy ring of lead was placed in the base. Lifting the base cap and looking in the base, you should see grayish lead.

Knock the shade. Grab the top of the glass shade and knock on the glass lightly. Because of its age, and the drying of the wax used to hold the glass together, the shade should rattle, says Fontaine. A firmer glass shade that doesn’t rattle could be a fake.

Ask for a guarantee: If you’re buying what you think is an authentic Tiffany lamp, make sure you get a money-back guarantee. If a shop is not willing to offer one, you might be spending a lot of money on something that could be a fake.